/**
 ****************************************************************************************
 *
 * @file mkimage.c
 *
 * @brief Utility for creating a firmware image for DA14580.
 *
 * Copyright (C) 2014. Dialog Semiconductor Ltd, unpublished work. This computer
 * program includes Confidential, Proprietary Information and is a Trade Secret of
 * Dialog Semiconductor Ltd.  All use, disclosure, and/or reproduction is prohibited
 * unless authorized in writing. All Rights Reserved.
 *
 * <bluetooth.support@diasemi.com> and contributors.
 *
 ****************************************************************************************
 */
#define _XOPEN_SOURCE 700
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#ifdef __linux__
#include <endian.h>
#endif
#include <string.h>
#include <errno.h>
#include <time.h>

#include "image.h"


#define MKIMAGE_VERSION "1.4"

/* uncomment to store multi-byte values in little-endian order */
#define MKIMAGE_LITTLE_ENDIAN


static void usage(const char* my_name)
{
	fprintf(stderr,
		"Version: " MKIMAGE_VERSION "\n"
		"Usage: %s in_file version_file out_file\n"
		"\n"
		"Prepend header to raw binary image 'in_file' (e.g. .bin file).\n"
		"The header contains versioning, timestamping and housekeeping\n"
		"information, which is partially extracted from header file\n"
		"'version_file'. The resulting image (e.g. .img file) is\n"
		"written to 'out_file'.\n"
		"\n"
		"The 'version_file' is normmaly stored at\n"
		"dk_apps/src/dialog/include/ble_580_sw_version.h and this\n"
		"program looks in it for definitions like below:\n"
		"\t#define DA14580_SW_VERSION \"v_3.0.3.221\"\n"
		"\t#define DA14580_SW_VERSION_DATE \"2014-06-30 17:56 \"\n"
		"\n"
		"Send bug reports, suggestions and comments to\n"
		"aristotelis.iordanidis@diasemi.com\n"
		"\n",
		my_name);
}


static inline void store32(uint8_t* buf, uint32_t val)
{
#ifdef MKIMAGE_LITTLE_ENDIAN
	buf[0] = val & 0xff;
	val >>= 8;
	buf[1] = val & 0xff;
	val >>= 8;
	buf[2] = val & 0xff;
	val >>= 8;
	buf[3] = val & 0xff;
#else
	buf[3] = val & 0xff;
	val >>= 8;
	buf[2] = val & 0xff;
	val >>= 8;
	buf[1] = val & 0xff;
	val >>= 8;
	buf[0] = val & 0xff;
#endif
}


static inline void store_crc(struct image_header* hdr, uint32_t crc)
{
	uint32_t val = crc;
	store32(hdr->CRC, val);
}


static int safe_write(int fd, const void* buf, size_t len)
{
	ssize_t n;

	do {
		n = write(fd, buf, len);
		if (n > 0) {
			len -= n;
			buf += n;
		} else if (n < 0  &&  errno != EINTR)
			return -1;
	} while (len);

	return 0;
}


/*
 * Look for a C string (i.e. string enclosed in "") inside text
 * NOTE: \" is not handled as escaped double quote
 *
 * Return a strdup'ed string; the caller SHOULD free it.
 */
char* find_cstring(const char* text)
{
	char* from, * to, * s;

	from = strchr(text, '"');
	if (!from)
		return NULL;

	to = strchr(++from, '"');
	if (!to)
		return NULL;

#ifdef __linux__
	s = strndup(from, to - from);
#else
	s = strdup(from);
	if (strlen(s)  >  to - from)
		s[to - from] = '\0';
#endif

	return s;
}


static void write_img_version(struct image_header* hdr, const char* s)
{
	/* skip any leading v_ */
	if ('v' == s[0]  &&  '_' == s[1])
		s += 2;
	snprintf((char*)hdr->version, sizeof hdr->version, "%s", s);
}

static void write_img_date(struct image_header* hdr, const char* s)
{
	struct tm tm;
	time_t secs;

	memset(&tm, 0, sizeof tm);
	tm.tm_isdst = -1;
#ifdef __linux__
	strptime(s, "%Y-%m-%d %H:%M", &tm);
#else
	sscanf(s, "%d-%d-%d %d:%d", &tm.tm_year, &tm.tm_mon, &tm.tm_mday,
			&tm.tm_hour, &tm.tm_min);
	tm.tm_year -= 1900;
	tm.tm_mon--;
#endif
	secs = mktime(&tm);
	if (-1 == secs)
		perror("mktime");
	store32(hdr->timestamp, secs);
}


/*
 * Parse f line by line and try to find the following patterns
 *
 * #define DA14580_SW_VERSION "v_3.0.3.221"
 * #define DA14580_SW_VERSION_DATE "2014-06-30 17:56 "
 *
 * We are interested in the two strings.
 */
static int parse_version_file(FILE* f, struct image_header* hdr)
{
	enum patterns {
		IMG_VERSION = 1,
		IMG_DATE = 2
	};
	unsigned patterns_left = IMG_VERSION | IMG_DATE;

	do {
		char* from, * s;
#ifdef __linux__
		size_t n, len;
		char* line;
#else
		char line[100];
#endif

#ifdef __linux__
		line = NULL;
		len = 0;
		n = getline(&line, &len, f);
		if (n < 0) {
			n = errno;
			free(line);
			return -n;
		}
#else
		if (fgets(line, sizeof line, f) == NULL) {
			return -errno;
		}
#endif

		if (patterns_left & IMG_VERSION) {
			from = strstr(line, "DA14580_SW_VERSION ");
			if (from) {
				s = find_cstring(from);
				if (s)
					patterns_left &= ~IMG_VERSION;
				write_img_version(hdr, s);
				free(s);
			}
		}
		if (patterns_left & IMG_DATE) {
			from = strstr(line, "DA14580_SW_VERSION_DATE ");
			if (from) {
				s = find_cstring(from);
				if (s)
					patterns_left &= ~IMG_DATE;
				write_img_date(hdr, s);
				free(s);
			}
		}

#ifdef __linux__
		free(line);
#endif
	} while (patterns_left);

	return 0;
}


static const uint32_t crc32_tab[] = {
	0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
	0xe963a535, 0x9e6495a3,	0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
	0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
	0xf3b97148, 0x84be41de,	0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
	0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,	0x14015c4f, 0x63066cd9,
	0xfa0f3d63, 0x8d080df5,	0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
	0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,	0x35b5a8fa, 0x42b2986c,
	0xdbbbc9d6, 0xacbcf940,	0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
	0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
	0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
	0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,	0x76dc4190, 0x01db7106,
	0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
	0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
	0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
	0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
	0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
	0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
	0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
	0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
	0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
	0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
	0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
	0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
	0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
	0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
	0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
	0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
	0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
	0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
	0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
	0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
	0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
	0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
	0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
	0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
	0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
	0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
	0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
	0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
	0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
	0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
	0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};

static uint8_t copy_buf[4096];
static int append_file(int outf, int inf, uint32_t* csum)
{
	ssize_t n;
	uint32_t crc32 = ~0;

	do {
		size_t count;
		int size;
		const uint8_t* data;

		count = sizeof copy_buf;
		n = read(inf, copy_buf, count);
		if (n < 0) {
			if (EINTR == errno)
				continue;
			else {
				perror("Error while reading input image");
				return -1;
			}
		}
		if (safe_write(outf, copy_buf, n)) {
			perror("writing image");
			return -1;
		}

		size = n;
		data = copy_buf;
		while (size--) {
			crc32 = crc32_tab[(crc32 ^ *data++) & 0xff]
				^ (crc32 >> 8);
		}
	} while (n != 0);

	/* no checksums for now */
	*csum = crc32 ^ ~0;

	return 0;
}


int main(int argc, const char* argv[])
{
	int inf = -1, outf = -1;
	FILE* verf = NULL;
	int oflags, n, res = EXIT_FAILURE;
	uint32_t csum;
	struct stat sbuf;
	struct image_header hdr;

	if (argc != 4) {
		usage(argv[0]);
		exit(EXIT_FAILURE);
	}

	memset(&hdr, 0xff, sizeof hdr);
	hdr.signature[0] = 0x70;
	hdr.signature[1] = 0x51;

	/* open input file and get its size */
	oflags = O_RDONLY;
#ifdef O_BINARY
	oflags |= O_BINARY;
#endif
	inf = open(argv[1], oflags);
	if (-1 == inf) {
		perror(argv[1]);
		exit(EXIT_FAILURE);
	}
	if (fstat(inf, &sbuf)) {
		perror(argv[1]);
		goto cleanup_and_exit;
	}
	store32(hdr.code_size, sbuf.st_size);

	/* open the version file and read version and timestamp */
	verf = fopen(argv[2], "r");
	if (NULL == verf) {
		perror(argv[2]);
		goto cleanup_and_exit;
	}
	n = parse_version_file(verf, &hdr);
	if (n < 0) {
		fprintf(stderr, "Could not parse %s: %s\n",
				argv[2], strerror(-n) );
		goto cleanup_and_exit;
	}

	/* open the output file */
	oflags = O_RDWR | O_CREAT | O_TRUNC;
#ifdef O_BINARY
	oflags |= O_BINARY;
#endif
	outf = open(argv[3], oflags, S_IRUSR | S_IWUSR);
	if (-1 == outf) {
		perror(argv[3]);
		goto cleanup_and_exit;
	}

	/* write current header, we'll update it before exiting */
	if (safe_write(outf, &hdr, sizeof hdr)) {
		perror(argv[3]);
		goto cleanup_and_exit;
	}

	if( append_file(outf, inf, &csum) )
		goto cleanup_and_exit;
	store_crc(&hdr, csum);

	/* write the header again, to set the checksum */
	if (lseek(outf, 0, SEEK_SET) == -1) {
		perror(argv[3]);
		goto cleanup_and_exit;
	}
	if (safe_write(outf, &hdr, sizeof hdr)) {
		perror(argv[3]);
		goto cleanup_and_exit;
	}

	res = EXIT_SUCCESS;

cleanup_and_exit:
	if (outf != -1) {
		if (close(outf))
			perror(argv[3]);
	}

	if (verf != NULL) {
		if (fclose(verf))
			perror(argv[2]);
	}

	if (inf != -1) {
		if (close(inf))
			perror(argv[1]);
	}

	exit(res);
}

